NASA released images from its probe of the large asteroid Vesta taken from the Dawn spacecraft on Thursday, and said the images support the theory that meteorites found on Earth came from it.
Vesta is considered to be a proto-planet, more akin to the Earth’s moon or a small planet than a typical asteroid. It’s unique in our solar system as a survivor of the era about 4.5 billion years ago, when the planets accreted from bodies much like Vesta to form Earth, Mars, Venus and Mercury. Like these planets, it has an iron core, a mantle and a surface crust.
Vesta resides in the asteroid belt between Mars and Jupiter, and was about 117 million miles from Earth when Dawn arrived in mid-2011. NASA has extended Dawn’s mission at Vesta by 40 days, allowing the spacecraft to continue its observations of the asteroid through August 26, before it leaves for the dwarf planet Ceres.
This rendering shows Vesta in perspective with its nearest planetary neighbor, Mars, as well as Mercury, Earth and the large planet-like body Ceres, which is the next stop on Dawn’s 3 billion mile mission (to see Vesta, minimize this caption using the arrow on the right).(NASA)
Images from Dawn’s framing camera were used to create this view of the Rheasilvia impact basin near Vesta’s south pole. The color code on the bottom image indicates the topography: the blue areas indicate depressions; the red areas show elevations.(NASA)
Vesta’s southern hemisphere shows a remarkable level of mineral diversity, as captured by Dawn’s spectrometer. Scientists believe the way the minerals are arrayed suggests that it melted early in its history.
These mineral samples, viewed through a polarizing microscope, are from asteroids that, scientists have now confirmed, come from Vesta. (NASA)
These three views of the Vibidia crater show the topography and composition of the 40-mile by 40-mile depression. The images used to create this composite view were taken during Dawn’s high-altitude mapping orbit, when the spacecraft was 420 miles above Vesta.(NASA)
This image shows a 2,000 square mile swath of Vesta’s southern hemisphere, with a focus on the Canuleia crater.(NASA)
Scientists aren’t sure what’s behind the mix of light and dark material at the rim of the Marcia crater. Explanations range from weathering, to impacts from nearby asteroids, to volcanic activity.
Dawn captured this close-up view of Vesta’s Rheasilvia impact basin during its low-altitude mapping orbit, which took it to about 130 miles above the asteroid.(NASA)
Images of areas around Vesta’s equator reveal craters that were filled in by materials thrown up in the collisions that created the Rheasilvia basin.(NASA)
Vesta’s south pole, as photographed by Dawn at a distance of about 1,700 miles.(NASA)